Key West Banded Butterflyfish on a Scuba Dive

Scuba diving in Key West is a popular tourist activity, and the local residents are equally enamored with the sport. With beautiful coral reefs, warm waters, and a wide variety of colorful and exotic aquatic life, it is an ideal setting for any scuba diver, whether a novice or an experienced pro. One of the fish that divers can expect to come across during their Key West dive is the Banded Butterflyfish, a small but striking reef fish native to the area.

The scientific name of the Banded Butterflyfish is Chaetodon striatus, which comes from a description of its teeth and literally translates to striped bristle tooth. In fact, they use their ten rows of teeth, which are unusually rough, to scrape and grasp at their invertebrate, coral, and tube worm diet, helping them hunt. Despite their intimidating dentition the Banded Butterflyfish socializes well with other fish and will even clean parasites off of them with their teeth. Nicknames for this deceptively cute fish include banded mariposas and Portuguese butterflies.

One way that this fish can be easily identified is by its coloring. It is white or pale yellow with think black horizontal bands painted down its body. The spiny pelvic fins, which also function as protection from predators such as eels or sharks, are also black with white or yellow spines on them. Juveniles briefly have different coloration. They are a translucent gray for the first day of their life and then a brownish color with a large black "false eye" spot on their back for another period of time, up until they reach about 2 inches. At that point they achieve their distinctive adult coloring, though they can grow up to another four inches. They have flat, round bodies and a longer, pointed face. They are thought to live about ten years.

These fish are most active in the daytime and generally hide in the reef at night to protect themselves from predators while they sleep. They don't often travel in large schools, preferring to be either solitary or to swim and hunt with their mate. However, a single female fish can produce an astounding number of eggs. During the spawning season between February and April, in the late evening as the sun is setting, a mating pair will release sperm and up to 4000 eggs all at once. After just a day they hatch. The larvae, which are covered bony armor for protection, also grow and mature quickly.

The Banded Butterflyfish is generally found off the southeastern coast of the United States, as well as the eastern coast of Central America and Brazil. They like warm, shallow waters and choose to live in rocky or reef areas where they can easily dart into small caves or between rocks for shelter. Though they aren't eaten by people, they are popular for aquariums due to their sociable nature and attractive appearance. They can be a bit shy around divers, but as long as the diver maintains a safe distance the fish will usually not try to hide.